Offline activation support + floating (#10)

artemlos · web-flow · commit 68aaaa4eb237 · 2019-01-31T10:36:10.000+01:00
* Add support for floating and overdraft

* Add SaveAsString and LoadFromString + refactor

* Fix bug in LoadFromString

* Remove redudant prints

* Add customer and dataobject

* Add comments

* Update example

* Fix a bug in LoadFromString

* Update readme
diff --git a/.idea/misc.xml b/.idea/misc.xml
diff --git a/.idea/workspace.xml b/.idea/workspace.xml
diff --git a/README.md b/README.md
@@ -5,6 +5,8 @@ This repository contains examples of how to verify license keys in Java applicat
 This library is continuously being improved. Please contact us at support@cryptolens.io should you have any questions.
 
 ## Example
+
+### Key verification
 The following example is similar to what is covered in the [key verification tutorial](https://help.cryptolens.io/examples/key-verification).
 
 Assuming you have referenced the `cryptolens.jar` file, the code below should generate successful result. A working project with the code below can be found in the [example-app](https://github.com/Cryptolens/cryptolens-java/tree/master/example-app) folder.
@@ -40,3 +42,15 @@ In order to adjust this code to your products, several parameters needs to be ch
 * `key` - the license key to be verified (above it's MPDWY-PQAOW-FKSCH-SGAAU).
 * `machine_code` - the unique id of the device, which may require root access. Note, this value is not the same as the one generated by the .NET client.
 
+### Offline activation (saving/loading licenses)
+Assuming the license key verification was successful, we can save the result in a file so that we can use it instead of contacting Cryptolens.
+
+```java
+String licenseString = license.SaveAsString();
+```
+
+When loading it back, we can use the code below:
+
+```java
+LicenseKey newLicense = LicenseKey.LoadFromString(RSAPubKey, licenseString);
+```
diff --git a/example-app/src/Main.java b/example-app/src/Main.java
@@ -4,16 +4,25 @@
 public class Main {
 
     public static void main(String[] args) {
-        String RSAPubKey = "<RSAKeyValue><Modulus>   sGbvxwdlDbqFXOMlVUnAF5ew0t0WpPW7rFpI5jHQOFkht/326dvh7t74RYeMpjy357NljouhpTLA3a6idnn4j6c3jmPWBkjZndGsPL4Bqm+fwE48nKpGPjkj4q/yzT4tHXBTyvaBjA8bVoCTnu+LiC4XEaLZRThGzIn5KQXKCigg6tQRy0GXE13XYFVz/x1mjFbT9/7dS8p85n8BuwlY5JvuBIQkKhuCNFfrUxBWyu87CFnXWjIupCD2VO/GbxaCvzrRjLZjAngLCMtZbYBALksqGPgTUN7ZM24XbPWyLtKPaXF2i4XRR9u6eTj5BfnLbKAU5PIVfjIS+vNYYogteQ==</Modulus><Exponent>AQAB</Exponent></RSAKeyValue>";
+        String RSAPubKey = "<RSAKeyValue><Modulus>sGbvxwdlDbqFXOMlVUnAF5ew0t0WpPW7rFpI5jHQOFkht/326dvh7t74RYeMpjy357NljouhpTLA3a6idnn4j6c3jmPWBkjZndGsPL4Bqm+fwE48nKpGPjkj4q/yzT4tHXBTyvaBjA8bVoCTnu+LiC4XEaLZRThGzIn5KQXKCigg6tQRy0GXE13XYFVz/x1mjFbT9/7dS8p85n8BuwlY5JvuBIQkKhuCNFfrUxBWyu87CFnXWjIupCD2VO/GbxaCvzrRjLZjAngLCMtZbYBALksqGPgTUN7ZM24XbPWyLtKPaXF2i4XRR9u6eTj5BfnLbKAU5PIVfjIS+vNYYogteQ==</Modulus><Exponent>AQAB</Exponent></RSAKeyValue>";
         String auth = "WyIyNjA5IiwiaWE5b0VFT3Q2eDlNR2FvbHBHK2VOYUZ4bzNjT3h5UkNrMCtiYnhPRSJd";
 
         LicenseKey license = Key.Activate(auth, RSAPubKey, new ActivateModel(3349, "ICVLD-VVSZR-ZTICT-YKGXL", Helpers.GetMachineCode()));
 
+        System.out.println(license);
+
         if (license == null || !Helpers.IsOnRightMachine(license)) {
             System.out.println("The license does not work.");
         } else {
             System.out.println("The license is valid!");
             System.out.println("It will expire: " + license.Expires);
+
+
+            // Saving and loading a license (for offline use)
+            String licenseString = license.SaveAsString();
+                LicenseKey newLicense = LicenseKey.LoadFromString(RSAPubKey, licenseString);
+
+            System.out.println(newLicense.Expires);
         }
     }
 }
diff --git a/pom.xml b/pom.xml
@@ -4,7 +4,7 @@
   <groupId>io.cryptolens</groupId>
   <artifactId>cryptolens</artifactId>
   <packaging>jar</packaging>
-  <version>1.3</version>
+  <version>1.4</version>
   <name>cryptolens</name>
   <description>A client api to access Cryptolens Licensing API.</description>
   <url>https://github.com/cryptolens/cryptolens-java</url>
diff --git a/src/main/java/io/cryptolens/methods/Helpers.java b/src/main/java/io/cryptolens/methods/Helpers.java
@@ -15,7 +15,7 @@ public class Helpers {
 
     /**
      * Returns a unique identifier of the device. Note, root access may be required.
-     * Furthermore, this method is not the same as the one used in our .NET client.
+     * Note, this method is not the same as the one used in our .NET client.
      */
     public static String GetMachineCode() {
 
@@ -27,16 +27,49 @@ public static String GetMachineCode() {
      * @returns True if the license is registered with this machine and False otherwise.
      */
     public static boolean IsOnRightMachine(LicenseKey license) {
+        return IsOnRightMachine(license, false);
+    }
+
+    /**
+     * Check if the device is registered with the license key.
+     * @param isFloatingLicense If this is a floating license, this parameter has to be set to true.
+     *                          You can enable floating licenses by setting @see ActivateModel.FloatingTimeInterval.
+     * @returns True if the license is registered with this machine and False otherwise.
+     */
+    public static boolean IsOnRightMachine(LicenseKey license, boolean isFloatingLicense) {
+        return IsOnRightMachine(license, isFloatingLicense, false);
+    }
+
+    /**
+     * Check if the device is registered with the license key.
+     * @param license The license key object
+     * @param isFloatingLicense If this is a floating license, this parameter has to be set to true.
+     *                          You can enable floating licenses by setting @see ActivateModel.FloatingTimeInterval.
+     * @param allowOverdraft If floating licensing is enabled with overdraft, this parameter should be set to true.
+     *                       You can enable overdraft by setting ActivateModel.MaxOverdraft" to a value greater than 0.
+     *
+     * @returns True if the license is registered with this machine and False otherwise.
+     */
+    public static boolean IsOnRightMachine(LicenseKey license, boolean isFloatingLicense, boolean allowOverdraft) {
 
         String current_mid = Helpers.GetMachineCode();
 
-        if (license.ActivatedMachines == null){
+        if (license == null || license.ActivatedMachines == null){
             return false;
         }
 
-        for (ActivatedMachine machine : license.ActivatedMachines) {
-            if(machine.Mid.equals(current_mid))
+        if(isFloatingLicense) {
+            if(license.ActivatedMachines.size() == 1 &&
+                    (license.ActivatedMachines.get(0).Mid.substring(9).equals(current_mid) ||
+                            allowOverdraft && license.ActivatedMachines.get(0).Mid.substring(19).equals(current_mid))) {
                 return true;
+            }
+        } else {
+
+            for (ActivatedMachine machine : license.ActivatedMachines) {
+                if(machine.Mid.equals(current_mid))
+                    return true;
+            }
         }
 
         return false;
diff --git a/src/main/java/io/cryptolens/methods/Key.java b/src/main/java/io/cryptolens/methods/Key.java
@@ -39,35 +39,7 @@ public static LicenseKey Activate (String token, String RSAPubKey, ActivateModel
             return null;
         }
 
-        try {
-            Base64.Decoder decoder = Base64.getDecoder();
-
-            byte[] licenseKey = decoder.decode(result.licenseKey);
-            byte[] signature = decoder.decode(result.signature);
-
-            // setting up the signatures
-            JavaSecuritySignatureVerifier signatureVerifier = new JavaSecuritySignatureVerifier();
-            int mstart = RSAPubKey.indexOf("<Modulus>");
-            int mend = RSAPubKey.indexOf("</Modulus>");
-            int estart = RSAPubKey.indexOf("<Exponent>");
-            int eend = RSAPubKey.indexOf("</Exponent>");
-            signatureVerifier.setModulusBase64(RSAPubKey.substring(mstart + 9, mend));
-            signatureVerifier.setExponentBase64(RSAPubKey.substring(estart + 10, eend));
-
-            if (!signatureVerifier.verify(licenseKey, signature)) {
-                System.err.println("Signature check failed");
-                return null;
-            }
-
-            String s = new String(licenseKey, StandardCharsets.UTF_8);
-            LicenseKey license = new Gson().fromJson(s, LicenseKey.class);
-            license.RawResponse = result.RawResponse;
-
-            return license;
-        } catch (Exception ex) {
-            System.err.println(ex.getStackTrace());
-        }
-        return null;
+        return LicenseKey.LoadFromString(RSAPubKey, result.RawResponse);
     }
 
 }
diff --git a/src/main/java/io/cryptolens/models/ActivatedMachine.java b/src/main/java/io/cryptolens/models/ActivatedMachine.java
@@ -1,6 +1,10 @@
 package io.cryptolens.models;
 
 public class ActivatedMachine {
+
+    /**
+     * The machine code.
+     */
     public String Mid;
     public String IP;
     public long Time;
diff --git a/src/main/java/io/cryptolens/models/Customer.java b/src/main/java/io/cryptolens/models/Customer.java
@@ -0,0 +1,9 @@
+package io.cryptolens.models;
+
+public class Customer {
+    public int Id;
+    public String Name;
+    public String Email;
+    public String CompanyName;
+    public long Created;
+}
diff --git a/src/main/java/io/cryptolens/models/DataObject.java b/src/main/java/io/cryptolens/models/DataObject.java
@@ -0,0 +1,8 @@
+package io.cryptolens.models;
+
+public class DataObject {
+    public int Id;
+    public String Name;
+    public String StringValue;
+    public int IntValue;
+}
diff --git a/src/main/java/io/cryptolens/models/LicenseKey.java b/src/main/java/io/cryptolens/models/LicenseKey.java
@@ -1,5 +1,10 @@
 package io.cryptolens.models;
 
+import com.google.gson.Gson;
+import io.cryptolens.JavaSecuritySignatureVerifier;
+
+import java.nio.charset.StandardCharsets;
+import java.util.Base64;
 import java.util.List;
 
 public class LicenseKey {
@@ -20,12 +25,63 @@ public class LicenseKey {
     public String Notes;
     public boolean Block;
     public long GlobalId;
-    //  private GsonCustomer Customer;
+    public Customer Customer;
     public List<ActivatedMachine> ActivatedMachines;
     public boolean TrialActivation;
     public int MaxNoOfMachines;
     //  private int AllowedMachines;
-//  private List<DataObject> DataObjects;
+    public List<DataObject> DataObjects;
     public long SignDate;
-    public String RawResponse;
+
+    /**
+     * Internal variable used to store the response.
+     */
+    protected String RawResponse;
+
+    /**
+     * Save the current license object as a string. You can load it again using @see LoadFromString.
+     * @return A string representing this license object object.
+     */
+    public String SaveAsString() {
+        return RawResponse;
+    }
+
+    /**
+     * Load a license string (created with @see SaveAsString) into a license object.
+     * Note, signature verification will be performed under the hood.
+     * @param RSAPubKey Your RSA Public Key, which can be found <a href="https://app.cryptolens.io/docs/api/v3/QuickStart">here</a>.
+     * @param licenseString The license key object stored as a string.
+     * @return A new license key object or null (if an error has occurred).
+     */
+    public static LicenseKey LoadFromString(String RSAPubKey, String licenseString) {
+
+        ActivateResult result = new Gson().fromJson(licenseString, ActivateResult.class);
+
+        Base64.Decoder decoder = Base64.getDecoder();
+
+        byte[] licenseKey = decoder.decode(result.licenseKey);
+        byte[] signature = decoder.decode(result.signature);
+
+        try {
+
+            JavaSecuritySignatureVerifier signatureVerifier = new JavaSecuritySignatureVerifier();
+            int mstart = RSAPubKey.indexOf("<Modulus>");
+            int mend = RSAPubKey.indexOf("</Modulus>");
+            int estart = RSAPubKey.indexOf("<Exponent>");
+            int eend = RSAPubKey.indexOf("</Exponent>");
+            signatureVerifier.setModulusBase64(RSAPubKey.substring(mstart + 9, mend));
+            signatureVerifier.setExponentBase64(RSAPubKey.substring(estart + 10, eend));
+
+            if (!signatureVerifier.verify(licenseKey, signature)) {
+                System.err.println("Signature check failed");
+                return null;
+            }
+        } catch(Exception ex) {System.err.println(ex.getStackTrace()); return null;}
+
+        String s = new String(licenseKey, StandardCharsets.UTF_8);
+        LicenseKey license = new Gson().fromJson(s, LicenseKey.class);
+        license.RawResponse = licenseString;
+
+        return license;
+    }
 }
diff --git a/src/test/java/io/cryptolens/AppTest.java b/src/test/java/io/cryptolens/AppTest.java
@@ -33,6 +33,10 @@ public static Test suite()
      */
     public void testApp()
     {
+        String test = "floating:test123";
+
+        System.out.println(test.substring(9));
+
         assertTrue( true );
 
     }
diff --git a/src/test/java/io/cryptolens/KeyTest.java b/src/test/java/io/cryptolens/KeyTest.java
@@ -49,8 +49,18 @@ public void testApp() throws Exception {
         } else {
             System.out.println("The license is valid!");
             System.out.println("It will expire: " + license.Expires);
+
+            System.out.println(license.Customer.Created);
+
+            String licenseString = license.SaveAsString();
+
+            LicenseKey newLicense = LicenseKey.LoadFromString(RSAPubKey, licenseString);
+
+            System.out.println(newLicense.Expires);
         }
 
+
+
         assertTrue( true );
 
     }
